昆布多糖硫酸酯对化疗药物治疗肝癌细胞的增敏作用

目的：探讨LAMS对肝癌细胞化疗的增敏作用。方法：以免疫组化法测定用LAMS前后肝癌细胞Bcl—2基因蛋白含量，以MTT法分别测定5—Fu、MTX、MMC、ADM、CTX与LAMS联合及单独治疗肝癌细胞的IC50以及有效作用时间。结果：LAMS使肝癌细胞Bcl—2基因蛋白表达下降，并使肝癌细胞对5—Fu、MTX、MMC、ADM、CTX的敏感性增加，有效作用时间延长。结论：LAMS可有效地增加肝癌细胞对5—Fu、MTX、MMC、ADM、CTX的敏感性。     

LAMS抑制肝癌细胞增殖和促凝活性的实验研究

目的：观察LAMS抑制肝癌细胞增殖和促凝活性的效果。方法：比较LAMS处理的肝癌细胞生长曲线、AgNoRs含量变化;用一步法APTT测定LAMS拮抗肝癌细胞分泌物的促凝血作用。结果：LAMS处理后的肝癌细胞增殖受抑制、AgNoRs数量减少,LAMS能拮抗肝癌细胞分泌物对APTT的影响。结论：LAMS可有效地抑制肝癌细胞增殖和促凝活性。     

褐藻淀粉硫酸酯对鹌鹑总胆固醇和HDL的影响

形成高胆固醇血症动物模型,使用褐藻淀粉硫酸酯可显著地降低血浆总胆固醇水平,并使HDL和HDL-C/TC比值升高。     

昆布多糖对大肠癌细胞生长转移能力抑制作用的研究

目的:研究昆布多糖(Laminarin)对结肠癌细胞生长、黏附和侵袭转移的抑制作用,为新药筛选提供理论依据。方法:采用同质、异质黏附,细胞分离及侵袭小室等试验技术检测不同含量昆布多糖对4种大肠癌细胞的细胞生物学特性的影响。结果:与对照组相比,在低含量药物作用时,基质黏附能力和同质黏附性,以及细胞分离能力均无明显变化。高含量药物作用后,sw480,sw620,HT29,LoVo基质黏附率分别为(0.292±0.21)%,(0.434±0.23)%,(0.428±0.43)%,(0.313±0.28)%,sw480,sw620,HT29,Lo-Vo同质黏附率分别为(10.6±2.3)%,(18.2±2.1)%,(25.5±3.0)%,(11.1±2.8)%,基质和同质黏附性均下降(P<0.05～0.01,t=4.217,7.105,10.571,2.196,8.245,3.452,10.563,5.231);sw480,sw620,HT29,LoVo细胞分离率增强,分别为(47.51±7.2)%,(45.26±8.3)%,(31.78±5.3)%,(45.226±7.5)%,(P<0.05～0.01,t=4.251,19.142,10.043,3.497);sw480,sw620,HT29,LoVo细胞穿过基底膜能力减弱,分别为(7.61±2.6),(20.4±3.1),(5.8±1.3),(15.1±3.6)个(P<0.01,t=11.541,12.534,16.143,23.427)。结论:昆布多糖可使细胞的恶性表型发生变化,使其侵袭转移能力受到抑制,并呈现剂量依赖性。     

硫酸昆布多糖在仓鼠胰腺癌肝转移模型中抑制作用的研究

目的观察硫酸昆布多糖(laminarinsulfate,LS)对仓鼠胰腺癌肝转移模型的抑制效果,阐明其抑制肿瘤机制。方法建立仓鼠胰腺癌肝转移模型,利用三种不同剂量LS对实验各组进行干预,应用昆布多糖、生理盐水作为对照组;对各组转移肿瘤重量、转移部位数、微血管密度(microvesseldensity,MVD)、抑瘤率进行比较。结果实验组三组肝转移癌平均称重(g)为3164±0577、315±0911、2905±1043;肿瘤转移部位数(个)为143±076、1438±0727、1368±0684;微血管密度(/hpf)分别为26143±447、21186±6327、18474±4903。对照组肝转移癌平均称重为昆布多糖组4867±0868,生理盐水组5147±094;肿瘤转移部位数昆布多糖组2167±1030;生理盐水组为189±099;微血管密度分别为昆布多糖组37583±7077,生理盐水组3429±7087。实验组抑瘤率分别为35%、353%、403%。经统计学分析表明实验组和对照组在肿瘤重量、肿瘤转移部位数、微血管密度等指标方面均存在显著差异(P<001)。抑瘤效果也随硫酸昆布多糖剂量增大渐增加。结论硫酸昆布多糖对肿瘤生长、转移、血管生成有明显抑制作用。     

昆布多糖和猴头多糖对实验性高血糖的防治作用

糖尿病患病率和死亡率逐年增高,高血糖还可诱发冠心病和动脉粥样硬化,它已严重地危害了人们的生命健康。本文探讨了猴头多糖(Hericium erinacaus Polysaccharide,简称HP),褐藻淀粉(Laminarin,LA)和褐藻酸钠(Sodium alginate,SA)对实验性高血糖的防治作用。     

Anti-β-glucan antibodies in healthy human subjects

Previous data by our group demonstrated the antifungal efficacy of a vaccine consisting of laminarin (β-(1,3)-glucan), conjugated with diphtheria toxoid, which generated protective anti-laminarin antibodies in mice. In this paper, we sought for the presence, isotype and subclass composition of natural anti-laminarin antibodies in an unselected population of human healthy subjects, in a comparison with antibodies directed against β-(1,6)-glucan (pustulan) and branched β-(1,3/1,6)-glucan (Pool 1) and mannan from Candida albicans. Almost all subjects showed detectable levels of anti-β-glucan antibodies, with IgG largely prevailing on IgM, little, if any, IgA and no IgE. However, the titer of anti-β-glucan antibodies was overall about 1 log lower than that of anti-mannan antibodies of the corresponding isotype. In particular, the level of anti-laminarin IgG was the lowest one, its geometrical mean titer (95% confidence interval, CI) being 1838 (1245–2714) as compared to 8157 (6067–10,931) and 3940 (2911–5332) for pustulan and Pool 1 fungal glucan, respectively. Analysis of IgG subclass composition showed that IgG2 was the prevalent subclass against any antigen, and again the concentration of anti-laminarin IgG2 was the lowest one, its geometrical mean concentration being 0.13 (0.07–0.24) μg/ml as compared to anti-pustulan and anti-Pool 1 glucan and mannan IgG2 levels, which were 0.33 (0.2–0.5), 1.35 (0.9–2.0), and 36.1 (25.2–51.3) μg/ml, respectively. These data show that anti-laminarin antibodies are present at low levels in humans as compared to other anti-β-glucan and, mostly, anti-mannan antibodies, and suggest that a protective antifungal vaccination in humans should attempt to tip the balance of antifungal antibodies in favour of the anti-laminarin ones.     

Lipopolysaccharide-mediated enhancement of zymosan phagocytosis by RAW 264.7 macrophages is independent of opsonins,laminarin, mannan,and complement receptor 3

Background

Fungal and bacterial coinfections are common in surgical settings; however, little is known about the effects of polymicrobial interactions on the cellular mechanisms involved in innate immune recognition and phagocytosis.

Materials and methods

Zymosan particles, cell wall derivatives of the yeast Saccharomyces cerevisiae, are used to model fungal interactions with host immune cells since they display carbohydrates, including beta-glucan, that are characteristic of fungal pathogens. Using in vitro cell culture, RAW 264.7 macrophages were challenged with zymosan, and phagocytosis determined via light microscopy. The effects of different concentrations of lipopolysaccharide (LPS) on zymosan phagocytosis were assessed. In addition, the transfer of supernatant from LPS-treated cells to naïve cells, the effects of soluble carbohydrates laminarin, mannan, or galactomannan, and the impact of complement receptor 3 (CR3) inhibition on phagocytosis were also determined.

Results

LPS enhanced phagocytosis of zymosan in a dose-dependent manner. Transfer of supernatants from LPS-primed cells to naïve cells had no effect on phagocytosis. Laminarin inhibited zymosan phagocytosis in naïve cells but not in LPS-primed cells. Neither mannan, galactomannan, nor CR3 inhibition had a significant effect on ingestion of unopsonized zymosan in naïve or LPS-treated cells.

Conclusions

Zymosan recognition by naïve cells is inhibited by laminarin, but not mannan, galactomannan, or CR3 inhibition. LPS enhancement of phagocytosis is laminarin insensitive and not mediated by supernatant factors or zymosan engagement by the mannose or CR3 receptors. Our data suggest alternative mechanisms of zymosan recognition in the presence and absence of LPS.     

褐藻淀粉和褐藻淀粉硫酸酯的制取、分析及生物活性比较

以改进方法从海带Laminaria japonica中提取褐藻淀粉,并人工磺化制得褐藻淀粉硫酸酯,得率分别为1%与2%,多糖含量为60.4%与31.1%,硫锰酯基含量为0.5%与10.2%,分子量为40000和80000。小鼠腹腔注射LD_(50)分别为980.00±110.215 mg/kg和689.80±80.93mg/kg,两种多糖均能明显促进小鼠腹腔巨噬细胞的吞噬功能,增强体液免疫功能,促进淋巴细胞转化,能对抗由环磷酰胺引起的白细胞下降和降低血清胆固醇等作用。褐藻淀粉还有对抗~(60)Coγ射线辐射,并对大鼠红细胞有明显促凝集作用,而褐藻淀粉硫酸酯对此作用不明显;但后者具有明显抗凝血,促进优球蛋白溶解等作用,而褐藻淀粉的作用不明显。     

褐藻淀粉硫酸酯对实验性动脉粥样硬化预防作用的机理研究

目的：探讨海洋药物褐藻淀粉硫酸酯对实验性动物粥样硬化预防作用的免疫学机理，方法：用酶联免疫吸附，放射免疫等方法测定了实验动物大鼠及鹌鹑的血清可溶性白介素2受体，免疫复合物，T淋巴细胞亚群，细胞因子及血脂代谢等指标。结果：高脂动物血脂代谢及免疫功能和细胞因子发生了明显紊乱，药物则有明显的调节作用，同时对脂肪酸代谢等亦有很强的调节作用。结论：褐藻淀粉硫酸酯对实验性动物粥样硬化的预防作用是对多种因素作用的结果。